A086766 - cp's OEIS frontend

A086766 a(n) = smallest r where (concatenation of n, r times with itself)*10 + 1 is a prime given by A087403(n), or 0 if no such number exists.

n	a(n)
1	1
2	3
3	1
4	1
5	11
6	1
7	1
8	2
9	2
10	1
11	9
12	3
13	1
14	5
15	1
16	3
17	15
18	1
19	1
20	2
21	1
22	60
23	3
24	1
25	1
26	2
27	1
28	1
29	5
30	5
31	1
32	2
33	1
34	6
35	12
36	3
37	12
38	3
39	5
40	1
41	2
42	1
43	1
44	5
45	3
46	1
47	0
48	2
49	1
50	9
51	2
52	1
53	6
54	1
55	6
56	18
57	1
58	3
59	45
60	1
61	6
62	3
63	1
64	1
65	2
66	1
67	0
68	3
69	1
70	1
71	2
72	3
73	4
74	8
75	1
76	1
77	6
78	2
79	36
80	96
81	1
82	1
83	5
84	304
85	6
86	2
87	6
88	1
89	2
90	2
91	1
92	2
93	5
94	1
95	6
96	5
97	1
98	2
99	1
100	0

[1, 3, 1, 1, 11, 1, 1, 2, 2, 1, 9, 3, 1, 5, 1, 3, 15, 1, 1, 2, 1, 60, 3, 1, 1, 2, 1, 1, 5, 5, 1, 2, 1, 6, 12, 3, 12, 3, 5, 1, 2, 1, 1, 5, 3, 1, 0, 2, 1, 9, 2, 1, 6, 1, 6, 18, 1, 3, 45, 1, 6, 3, 1, 1, 2, 1, 0, 3, 1, 1, 2, 3, 4, 8, 1, 1, 6, 2, 36, 96, 1, 1, 5, 304, 6, 2, 6, 1, 2, 2, 1, 2, 5, 1, 6, 5, 1, 2, 1, 0]

cp's OEIS Frontend

A086766 a(n) = smallest r where (concatenation of n, r times with itself)*10 + 1 is a prime given by A087403(n), or 0 if no such number exists.

Table of values

List of values

n	a(n)
1	1
2	3
3	1
4	1
5	11
6	1
7	1
8	2
9	2
10	1
11	9
12	3
13	1
14	5
15	1
16	3
17	15
18	1
19	1
20	2
21	1
22	60
23	3
24	1
25	1
26	2
27	1
28	1
29	5
30	5
31	1
32	2
33	1
34	6
35	12
36	3
37	12
38	3
39	5
40	1
41	2
42	1
43	1
44	5
45	3
46	1
47	0
48	2
49	1
50	9
51	2
52	1
53	6
54	1
55	6
56	18
57	1
58	3
59	45
60	1
61	6
62	3
63	1
64	1
65	2
66	1
67	0
68	3
69	1
70	1
71	2
72	3
73	4
74	8
75	1
76	1
77	6
78	2
79	36
80	96
81	1
82	1
83	5
84	304
85	6
86	2
87	6
88	1
89	2
90	2
91	1
92	2
93	5
94	1
95	6
96	5
97	1
98	2
99	1
100	0

n	a(n)
1	1
2	3
3	1
4	1
5	11
6	1
7	1
8	2
9	2
10	1
11	9
12	3
13	1
14	5
15	1
16	3
17	15
18	1
19	1
20	2
21	1
22	60
23	3
24	1
25	1
26	2
27	1
28	1
29	5
30	5
31	1
32	2
33	1
34	6
35	12
36	3
37	12
38	3
39	5
40	1
41	2
42	1
43	1
44	5
45	3
46	1
47	0
48	2
49	1
50	9
51	2
52	1
53	6
54	1
55	6
56	18
57	1
58	3
59	45
60	1
61	6
62	3
63	1
64	1
65	2
66	1
67	0
68	3
69	1
70	1
71	2
72	3
73	4
74	8
75	1
76	1
77	6
78	2
79	36
80	96
81	1
82	1
83	5
84	304
85	6
86	2
87	6
88	1
89	2
90	2
91	1
92	2
93	5
94	1
95	6
96	5
97	1
98	2
99	1
100	0

n	a(n)
1	1
2	3
3	1
4	1
5	11
6	1
7	1
8	2
9	2
10	1
11	9
12	3
13	1
14	5
15	1
16	3
17	15
18	1
19	1
20	2
21	1
22	60
23	3
24	1
25	1
26	2
27	1
28	1
29	5
30	5
31	1
32	2
33	1
34	6
35	12
36	3
37	12
38	3
39	5
40	1
41	2
42	1
43	1
44	5
45	3
46	1
47	0
48	2
49	1
50	9
51	2
52	1
53	6
54	1
55	6
56	18
57	1
58	3
59	45
60	1
61	6
62	3
63	1
64	1
65	2
66	1
67	0
68	3
69	1
70	1
71	2
72	3
73	4
74	8
75	1
76	1
77	6
78	2
79	36
80	96
81	1
82	1
83	5
84	304
85	6
86	2
87	6
88	1
89	2
90	2
91	1
92	2
93	5
94	1
95	6
96	5
97	1
98	2
99	1
100	0